More details please.

There is no column-level locking at the table level in Access, nor in SQL Server for that matter.  You can, of course, do it at the form level: create a form that locks certain fields.  If you need locking at the table level, know that data that need to be locked should probably be put in another table, one that can be made inaccessible to users.

That is one of the use cases Richard talks about for ONE-TO-ONE relationships in this RELATIONSHIPS Tech Help video at about 6:30.  He also discusses it in other videos.  When designing table structure, each table should have a singular type of data.  In your case, the protected data is different than the un-protected data and should be in its own table.

Do it in a form. NEVER let your end users work directly in tables and queries. FORMS. FORMS. FORMS.

I appreciate all the input. sorry i was not able to give an example before. Ive been tied up with work. I will look into all the information provided